Improvement in methods of compressing and liquefying nitrous oxide and other gases



WILBUB F. JOHNSTON AND WILLIAM A.VJOHNSTON, OF BROOKLYN, Y.

IIVIPHVEMENT IN IVIETHUDS UF CONIPRESSING AND LIQUEFYING NITHUS XIDE ANDOTHER GASES.

Specification forming part of Letters Patent No. l20,978,74datedNovember 14, 1871.

To all whom t may concern:

Be it knownthat we, WILBUR-F. JOHNSTON and WILLIAM: A. JOHNSTON, ofBrooklyn, in the county of Kings and State of New York, have inventedcertain Improvements in Gas-Liquefying Apparatus, of Which the followingis a specication:

The essential parts of this apparatus are, irst, a hydraulic pump;second, one or more strong tanks, third, a receiver or bottle into Whichthe product of the apparatus is collected.

In the annexed drawing, B is thehydraulic pump 5 A and G', strong tanks,of which G is much the stronger. H'is a recevingloottle or tankconnected With G. O is a pipe connecting pump B with tank A. N is a pipeconnecting G with pump B. D, F, and G are stop-valves. K is a glassgauge-pipe. M is a safetyevalve. L is a valve through which gas isadmitted intoA the apparatus. E is a pipe closed by the stop-cock, fromwhich the tank 'can be emptied. Of course such liquid will be used intransmitting the pressure as Will be least operated upon by the.corrosive powers of the material compressed.

In liquefying nitrous-oxide gas We rst fill both v tanks A and G and allthe pipes With Water for the purpose of expelling the air from them. Wenext admit nitrous-oxide gas through L, at the same time letting olf theWater from both tanks through E. When A and G are filled with gas weclose L, E, and F,'and at the same time open D and G and set thehydraulic pump in motion. As the tank A is filled with water the gas isforced-through G into the tank G', which is very much smaller than A. Wethen close D and G and open F. The pump still ruiming, the Water isforced through N into GJ, Which Will stand a much greater strain thancould be safely borne by tank A. The gas is still forced before theWater until it is shown in the glass tube K. Then the stop-cock I isopened, and the gas soon fills the bottle H, When I is again closed. Theoperation may noW be again repeated, after irst filling the apparatusWith Water.

By the use of a hydraulic pump We avoid the diculty that continuallyarises Where compres sion is attempted by an air-pump. We also gaingreatly in speed and efficiency of operation. By making use of tWo ormore tanks instead of one large one We secure great economy ofconstruction, as it would be enormously expensive, if not impossible, tomake a tank capable of holding one or more hundred gallons and still ofsufficient strength to stand the strain needful for the completion ofthe process of liquefaction.

We claim- 1. The combination of a hydraulic pump with one or more tanks,substantially as described, and for the purposes set forth.

2. In apparatus for condensing gas or eeriform matter, the use of aseries of tanks of varying strength, substantially as and for thepurposes set forth.

W. F. JOHNSTON. W. A. JOHNSTON. Witnesses:

D. D. WHITNEY,

J. C. WHITNEY. (46)

